1. Field of the Invention
The present invention relates to a heat-dissipating module and a lamp having the same. More particularly, the present invention relates to a heat-dissipating module having vertical airflow channels and a lamp having such a heat-dissipating module.
2. Description of Prior Art
With the advancement of science and technology, light emitting diodes (LED) are widely used in various lamps to replace traditional incandescent bulbs because the LEDs have low electricity consumption and long lifetime. However, each LED generates heat when emitting light. If the thus-generated heat is not dissipated to the outside, the heat will be accumulated in the LED to raise its temperature. As a result, electronic components in the LED will suffer damage or even burn down.
In order to solve the problem relating to the heat dissipation of the LEDs, the existing solution is to provide a heat-dissipating module made by aluminum extrusion. Such an aluminum-extruded heat-dissipating module includes a base and a plurality of fins integrally formed with the base. After the base of the heat-dissipating module is brought into thermal contact with the LEDs, the heat generated by the LEDs will be conducted to the base and then dissipated to the outside via the fins.
However, such a conventional heat-dissipating module has the following problems.
First, since the conventional heat-dissipating module is made by aluminum extrusion, a greater amount of aluminum material has to be used, which increases the weight of the heat-dissipating module.
Second, during the manufacturing process, the traditional aluminum-extruded heat-dissipating module is subjected to an extending step and a cutting step. As a result, the surface of the heat-dissipating module to be brought into thermal contact with a heat source is not flat sufficiently. Thus, heat-conducting paste is often applied to the surface to thereby increase the degree of adhesion and heat-conducting efficiency. However, the application of heat-conducting paste inevitably increases the working hours and production cost.
Third, in the conventional heat-dissipating module, the fins are integrally formed with the base by extrusion. Thus, airflow below the base cannot directly heat-exchange with the fins above the base because the air is blocked by the base. On the other hand, since light-emitting elements such as LEDs are usually mounted below the base, the heat generated by the light-emitting elements can be only conducted to the fins above the base by thermal conduction in metallic materials. Then, the heat conducted to the fins is dissipated by the airflow above the base. Therefore, the heat-dissipating effect is so limited.
Fourth, in the conventional aluminum-extruded heat-dissipating module, since the fins are extruded to form on the periphery of the base, the heat-dissipating rate in the central portion of the base is smaller than that in the peripheral portion of the base. Furthermore, the airflow above the base cannot pass through the fins at the peripheral portion of the base to flow over the central portion of the base. Thus, such an insufficient airflow has a poor effect on dissipating the heat in the central portion of the base. As a result, the heat accumulated in the central portion of the conventional heat-dissipating module cannot be dissipated easily. Accordingly, in consideration of the low heat-dissipating effect in the central portion of the base, the heat-generating light-emitting elements are usually arranged on the periphery of the base, which restricts the degree of freedom in arranging the light-emitting elements on the base.
Thus, it is an important issue for the present inventor to solve the above-mentioned problems.